Subject: Re: m50tu oil leak (update) Author: yaofeng : member since November, 2005 : 1533 posts Posted on: 2008-05-31 18:12:01

I still have the original 95 m50tu engine in the garage. The engine has the aluminum timing chain guide, or tensioner as BMW calls it. When I bought the car two years ago for reasons I cannot remember anymore I have to cut it to remove the tensioner (or guide).



BMW replaced the aluminum guide with one plastic for later model m50tu's. I think that is why I cut the aluminum tensioner because I know I can install the plastic one as it will bend and snap into place but not the aluminum tensioner. Of course there must be a better way to install the tensioner but I didn't know then. Still don't know how now if I had to do it with the aluminum tensioner.

With the change of the tensioner from aluminum to plastic the tensioner plug was also changed.


The top one is for the plastic tensioner. The bottom one is for the aluminum tensioner.

A year ago I replaced the engine with one from a 93. The 93 engine has the aluminum tensioner. I didn't touch the tensioner or plug. As it turned out it is the source of the engine oil leak.

So I removed the offending plug today,


and replaced it with the later style plug,


Of course I used the plug extender (for lack of better terms I call the piece in contact with the tensioner) which matches with the aluminum tensioner since the 93 engine now on the car has the aluminum version.

So after the tensioner plug replacement, engine degrease, hose off and test drive, this is what I see.


The tensioner plug is not dripping oil anymore. But wait, after I shut the engine off the r134 hose connections to the AC compressor is oozing oil and bubbling. I tried to tighten the hose connection nut with the allen key but it will not turn which means it is already tight.

No wonder the AC is not working. But why is it bubbling from the connector bolt?

AIM: yaofeng4249
'95 540ia converted to 6 speed, 144k built 7/94 w/ 66k 93 E32 V8 Nikasil engine

• m50tu oil leak (pic) - yaofeng 2008-05-12 21:27:13 (234 views)
  • Re: m50tu oil leak (update) (pic) - yaofeng 2008-05-31 18:12:01 (139 views)
  • Re: m50tu oil leak - Shayne 2008-05-26 03:52:45 (74 views)
    • Re: m50tu oil leak - yaofeng 2008-05-26 07:07:24 (68 views)
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        • Re: m50tu oil leak (pic) - yaofeng 2008-05-30 18:23:13 (111 views)
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          • Re: Oil likes to drip down and to the rear (pic) - yaofeng 2008-05-26 21:22:48 (104 views)
            • I hated re-using it - kfister 2008-05-26 22:28:13 (61 views)
  • Re: m50tu oil leak - 525ialex1993auto 2008-05-25 23:58:42 (64 views)
  • Me too. - bobbert 2008-05-13 14:17:35 (72 views)